Unit 1 Biology

Question 1

Millimetre = ?

Answer 1

1x 10^-3

Question 2

Micrometer = ?

Answer 2

1x 10^-6

Question 3

Nano meter= ?

Answer 3

1x 10^-9

Question 4

Magnification formula

Answer 4

Magnification = size of image/ size of object

Question 5

Differences between light and electron microscopes

Answer 5

You can see colour in a light microscope but not in an electron microscope. Electron microscopes have a much higher magnification and produce 3d images

Question 6

Name 3 parts of an animal cell

Answer 6

Mitochondria
Ribosome
Cytoplasm
Nucleus
Cell membrane

Question 7

Name 3 unique parts of a plant cell

Answer 7

Cell wall
Vacuole
Chloroplasts

Question 8

How is DNA stored in bacterial cells

Answer 8

In plasmids and in DNA loop

Question 9

How is a red blood cell specialised to do its job

Answer 9

Disc shaped for larger surface area
Has haemoglobin to carry oxygen. No mitochondria for greater area for haemoglobin

Question 10

How is a muscle cell specialised to do its job

Answer 10

Lots of mitochondria for respiration.
Can hold glycogen.
Special proteins that can slide over each other for contraction

Question 11

How is a Nerve cell specialised to do its job

Answer 11

Very long so it can send the signal further.
Lots of mitochondria in the ends so neurotransmitters can do their job.

Question 12

How is a root hair cell specialised to do its job

Answer 12

No chloroplasts so more mitochondria for energy. Large SA to volume ratio so lots of water can move in.

Question 13

How is Xylem specialised to do its job

Answer 13

Lignin forms on it and kills it but creates large hollow tubes to allow water and minerals to pass through

Question 14

In animals, when does cell differentiation normally take place

Answer 14

When you are an embryo and the stem cells specialise

Question 14

How is phloem specialised to do its job

Answer 14

Has sieve plates to help the movement of substances from cell to cell.
More energy is produced due to the companion cells on it

Question 15

Differences between embryonic and adult stem cells

Answer 15

Embryonic stem cells form when an egg and sperm cell form a zygote. Can differentiate into almost all cells so many cures like to Alzheimer’s can be made. Adult stem cells are found in bone marrow

Question 16

What is the stem cell in plants called

Answer 16

Meristem tissue. Found in root and shoot tips

Question 17

Benefits of stem cell research

Answer 17

Can be used to replace damaged or diseased body parts. We can use unwanted embryos to avoid people being upset. Helps with researching differentiation.

Question 18

Problems with stem cell research

Answer 18

Removal of stem cells results in the destruction of the embryo. Time and money could be spent on more important parts of medicine. Disease can be transferred of the original stem cell is infected. Religious and ethical concerns

Question 19

How many pairs of chromosomes are there in your body

Answer 19

23 (46 single chromosomes in each cell)

Question 20

What is a gene

Answer 20

A small strand of DNA that codes for a protein and controls characteristics

Question 21

Stage 1 of mitosis

Answer 21

Cell grows and mitochondria and ribosome numbers increase. DNA is replicated

Question 22

Stage 2 of mitosis

Answer 22

Chromosomes line up in the Center and move to either side of the cell to separate

Question 23

Stage 3 of mitosis

Answer 23

Cytoplasm divides and two identical daughter cells are formed

Question 24

2 ways to grow microorganism cultures

Answer 24

Agar gel plate or nutrient broth

Question 25

How to sterilise equipment

Answer 25

Use an autoclave oven or UV light. Do this to the inoculating loop.

Question 26

Why aren’t bacteria cultures grown at over 25 degrees

Answer 26

Dangerous bacteria can grow over this temperature

Question 27

How to calculate the amount of bacteria grown

Answer 27

Starting number of bacteria x 2^number if divisions

Question 28

Name of zone formed around bacteria when there is a disinfectant on it

Answer 28

Inhibition zone

Question 29

Definition of diffusion

Answer 29

The movement of particles from an area of high concentration to and area of low concentration

Question 30

3 factors affecting diffusion

Answer 30

Concentration gradient.
Temperature.
Surface area of membrane.

Question 31

How can single cells organisms carry out diffusion

Answer 31

Small SA to volume ratio

Question 32

Why is a thin membrane good for diffusion

Answer 32

Small distance for diffusion

Question 33

Why is a good blood supply good for diffusion

Answer 33

Steep concentration gradient

Question 34

Examples of good diffusion

Answer 34

Root hair cell
Alveoli in lungs
Villi in small intestine

Question 35

What is osmosis

Answer 35

The movement of water from a more concentrated area to a less concentrated area across a partially permeable membrane

Question 36

What do we call it when the solution is
a.) higher externally
b.) lower externally
c.) the same

Answer 36

a.)hypertonic
b.)hypotonic
c.)isotonic

Question 37

What is the risk for osmosis with high glucose levels

Answer 37

The cells can become shrivelled as there is a low amount of water outside it

Question 38

How is active transport different to osmosis and diffusion

Answer 38

It is an active process so it requires energy to take place. It goes against the concentration gradient.

Question 39

Examples of active transport in both animals and plants

Answer 39

Plant- root hair cell takes mineral ions and water from the soil
Animals- moving glucose from the gut up to the bloodstream

Question 40

Eukaryotic vs prokaryotic

Answer 40

Eukaryotic = newer animal and plant . Much bigger
Prokaryotic= older bacteria. Much smaller